FIELD OF THE INVENTION
The invention relates to a device for connecting a machine element to a structural member movable about a longitudinal axis thereof so that the machine element and the structural member are secured against relative rotation. In particular, the invention relates to a device for clamping a machine element at a circumference of a hollow shaft preferably of a sheet-fed printing press so that the machine element is fixed, at one of an infinite number of phase-angle settings, against torsion relative to the hollow shaft, the hollow shaft being movable about a longitudinal axis thereof for clamping a gripper stop on a gripper bar of the sheet-fed printing press.
Clamping a machine element on a structural member in an infinitely adjustable manner with respect to the angle of rotation thereof so as to withstand a torque load and, in particular, recurring loads, without varying the position of the machine element with respect to the structural member, requires great frictional forces between the mutually engaging clamping surfaces and correspondingly great radial clamping forces. The reliable mounting or supporting of the machine element on the structural member so that it is fixed against torsion relative thereto is rendered difficult by the fact that the cross section of the structural member is round or rounded at the clamping location to permit the machine element to be clamped in any one of an infinite number of angular positions or settings, and yet there must be no occurrence of any deformation of the clamped cross-section thereof. Heretofore known are clamping straps which embrace or are slung or looped about the structural member at the clamping location. These known clamping straps are formed with thickened ends which are disposed opposite one another with respect to a gap extending approximately in an axial plane wherein the longitudinal axis of the structural member is disposed and which are clampable with respect to one another perpendicularly to the gap by means of one clamping bolt or a plurality thereof, so that the clamping strap is pressed against the circumference of the structural member. With such a clamping strap, the clamping forces acting in various circumferential regions radially upon the structural member are very different from one another the clamping forces reaching peak values primarily at the edges of the gap so that hollow shafts suffer deformations quite readily at the cross-section thereof, which results in the impairment of inner bearings. Such disadvantages are primarily to be avoided with respect to gripper bars in printing presses or other sheet-processing machines wherein, by means of such conventional clamping straps, stops for sheet grippers are fastened onto a hollow shaft wherein a control shaft is mounted possibly without play, said control shaft being provided for the sheet grippers and being driven so as to swing about the longitudinal axis thereof. Deformations of the hollow shaft disrupt the smooth operation of the inner shaft. In printing-press technology, the relatively bulky or cumbersome form of construction which hinders the motion of other structural members represents another disadvantage. Clamping straps of the conventional type have a relatively large cross-section in the region thereof at which they embrace or are slung about the shaft and, above all, at the thickened ends thereof, thereby, in connection with high accelerations, producing a high moment of inertia which has a negative effect upon the dynamic gripper behavior.
Although it has been known heretofore to use clips for connecting the ends of hoses formed of flexible material or for connecting a hose end and a fitting, as disclosed, for example, in the German Published Non-Prosecuted Patent Application (DE-OS) 26 19 179, such clips are not suited for providing a torque-transmitting connection.